Molality is obtained by dividing the number of moles of solute by the mass in kilogram of the solvent. None of the dimensions is dependent in temperature. On the other hand, molarity is obtained by dividing the number of moles of solute by the volume in liters of the solution. Volume is temperature dependent.
Answer: B. 1:2
Explanation: Beryllium and chlorine forms a binary ionic compound. Ionic compound is formed when a metal loses its electrons to a receiving non metal. Beryllium (metal) has two valence electrons while chlorine (nonmetal) has seven valence electrons, and so a beryllium atom has to give out its two valence electrons to attain a duplet stable structure while a chlorine atom will gain one electron to attain its stable octet structure. In the reaction between beryllium and chlorine, two atoms of chlorine have to accept the two electrons from one beryllium atom to attain their stable octet structure.
The formula of the compound formed is BeCl2.